The Seasonal Dipter Larval Species Richness During Decomposition and Comparisons to Current Successional Models

Forensic entomology is the study of insects and related arthropods as applied to legal proceedings. The first documented case using forensic entomology was reported in the 13th century in “The Washing Away of Wrongs” by Sung Tzu, a Chinese lawyer. It wasn’t until the 19th century during exhumations in France, that the important role that maggots play in decomposition was discovered. In general, there are four or five stages of decay: Fresh, Bloated, Decay (which can sometimes be further divided into active and advanced decay), and the Skeletal/Dry stage. Carrion does not adhere to these stages strictly, and the process can be flexible. Depending on the climate, some stages can be skipped. The purpose of this experiment is to do a comprehensive assessment of the Diptera larval species present during decomposition throughout the summer and winter. Summer 2009 had a higher species richness and diversity than summer 2017. Piophillidae and Phoridae were present in the adult successional models but were absent in the larval model. The only Muscidae species present was Hydrotaea aenescens during the larval assessment. Calliphoridae was present with the largest number of different species. Lucilia spp. was present during the larval assessment but not the adult assessment. Winter 2010 had a higher species richness and diversity than winter 2018. Only one species of Calliphoridae Calliphora livida was present in the winter larval assessment. Summer 2017 had a higher species richness than winter 2018. Winter had a lower accumulated degree days than summer which could have resulted in the lack of diversity. Winter most likely had less adult presence than summer due to the temperatures and therefore had a lower diversity. There was more rain in the winter than the summer which likely deterred some Diptera from coming to the carrion.